Mitsubishi Montero (2002-2004). Manual - part 353

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-459

NOTE: Also check intermediate connectors D-26, D-28, junc-
tion block connectors D-207 and D-221 for loose, corroded, or 
damaged terminals, or terminals pushed back in the connector. 
If intermediate connector D-26, D-28, junction block connector 
D-207 or D-221 is damaged, repair or replace the damaged 
component(s) as described in GROUP, Harness Connector 
Inspection 

P.00E-2

.

Q: Is the wiring harness between dome light connector F-

03 (terminal 1) and fusible link (1) in good condition?
YES : No action to be taken.
NO :  Repair the wiring harness. Verify that the dome light 

illuminates normally.

AC204188

CONNECTORS : D-26, D-28

D-28

AH

D-26

D-28

D-26

2 3

27

32

28

33

16

15

4 5

19

18

29

17

34

7 8

35

22

21

9 10

30

36

31

37

25

24

23

6

20

1

14

26

11

13

12

38

2 3

1

7

6

12

11

8

13

5

4

9 10

AC204191

CONNECTORS : D-207, D-221

D-207

AB

HARNESS SIDE

HARNESS SIDE

D-221

D-207

D-221

3

1

4

6 5

7

8

2

1

2

3

4

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-460

INSPECTION PROCEDURE M-2: Interior Light: Dome light dimming function does not work normally.

NOTE: This troubleshooting procedure requires the 
use of scan tool MB991502 and SWS monitor kit 
MB991862. For details on how to use the SWS mon-
itor, refer to "How to use SWS monitor 

P.54Ba-8

."

.

CIRCUIT OPERATION
The ETACS-ECU operates the dome light dimming 
function according to the following switches:

• Ignition switch (IG1)

• Key reminder switch

• Front door switches

• Driver's door lock actuator switch

.

TECHNICAL DESCRIPTION (COMMENT)
Is the dome lights do not dim normally, the input cir-
cuits from the switches described in "CIRCUIT 
OPERATION" or the ETACS-ECU may be defective.

.

TROUBLESHOOTING HINTS

• The key reminder switch may be defective

• The door switches may be defective

• The driver’s door lock actuator switch may be 

defective

• The ETACS-ECU may be defective

• The wiring harness or connectors may have 

loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB991502: Scan Tool (MUT-II)

• MB991862: SWS monitor kit

STEP 1. Verify the dome light.
If the dome light switch are moved to the "door interlock posi-
tion", the dome light should illuminate when either door is 
opened.
Q: Do the dome light illuminate normally?

YES : Go to Step 2.
NO :  Refer to Inspection Procedure M-1 "The dome light do 

not illuminate or go out normally 

P.54Bb-450

."

Interior Light Dimming Function

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-461

STEP 2. Use scan tool MB991502 to select "ECU COMM 
CHK" on the SWS monitor display.
Check the ETACS-ECU.

CAUTION

To prevent damage to scan tool MB991502, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector 

(16-pin).

(2) Connect SWS monitor kit MB991862 to the data link 

connector (13-pin).

(3) Turn the ignition switch to the "LOCK" (OFF) position.
(4) Operate scan tool MB991502 according to the procedure 

below to display "ECU COMM CHK."

1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "SWS MONITOR."
4. Select "ECU COMM CHK."

(5) Scan tool MB991502 should show "OK" on the "ECU 

COMM CHK" menu for the "ETACS ECU" menu.

Q: Is "OK" displayed on the "ETACS ECU" menu?

YES : Go to Step 3.
NO :  Refer to Inspection Procedure A-3 "Communication 

with ETACS-ECU is not possible 

P.54Bb-25

."

AC204222AB

16-pin

13-pin

MB991502

MB991862

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-462

STEP 3. Check the input signal by using "DATA LIST" 
menu of the SWS monitor.
Check the input signals from the following switches: 

• Ignition switch: ON or START

• Driver’s door: open

Operate scan tool MB991502 according to the procedure below 
to display "ETACS ECU."

1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "SWS MONITOR."
4. Select "DATA LIST."
5. Select "ETACS ECU."

Check that normal conditions are displayed on the items 
described in the table below.

Q: Are normal conditions displayed on the "IG SW (IG1)" 

and "FRONT DOOR SW"?
YES : Go to Step 4.
NO : 

• Normal condition is not displayed on the "IG SW 

(IG1)": Refer to Inspection Procedure O-2 
"ETACS-ECU does not receive any signal from 
the ignition switch (IG1) 

P.54Bc-7

."

• Normal condition is not displayed on the "FRONT 

DOOR SW": Refer to Inspection Procedure O-5 
"ETACS-ECU does not receive any signal from 
the driver's or the front passenger's door switch 

P.54Bc-23

."

ITEM NO.

ITEM NAME

NORMAL 
CONDITION

ITEM 30

IG SW (IG1)

ON

ITEM 32

FRONT DOOR SW

ON

AC204222AB

16-pin

13-pin

MB991502

MB991862